To determine the source of lipoprotein(a) (Lp(a)) using amino acids labeled with stable isotopes, apoprotein B and apo(a) kinetics will be examined using [15N]-glycine, [2H4]-lysine and [13C]leucine incorporation into the apoproteins. Precursor-product relationships will be examined using curve peeling techniques. Fractional synthetic & catabolic rates will be examined during the fed & fasted states. This will improve our understanding of the source and regulation of the unusual lipoprotein Lp(a).